The opening of unused TV band spectrum for usage by unlicensed TV band devices has created a requirement for a television band spectrum that can dynamically identify white spaces within the VHF/UHF TV band spectrum.
Sensing white spaces within the VHF/UHF TV band spectrum is a vital issue for the operation of unlicensed TV band devices. Protection of licensed incumbent operators such as DTV broadcasters and wireless microphone operators is mandated by the Federal Communications Commission (FCC). The sensing requirements mandated by the FCC are quite stringent, and requires that the TV band device be provided with information about the quality of the available white space to allow the TV band device to utilize that white space efficiently. Because of the FCC's stringent sensing threshold (−114 dB), sensing the television band spectrum for available white space is an extremely challenging task to perform at reasonable cost. Existing low cost technology such as the standard television tuner cannot meet the FCC sensing threshold.
There therefore exists a need for a radio frequency front end for a television band receiver and spectrum sensor for identifying white spaces within the VHF/UHF TV band spectrum.